Measurement of the q2 dependence of the Hadronic Form Factor in D0 --> K- e+ nu_e decays

TL;DR

This paper reports a preliminary measurement of how the decay rate of D0 to K- e+ nu_e varies with q2, providing insights into the hadronic form factor crucial for understanding charm semileptonic decays.

Contribution

It introduces a measurement of the q2 dependence of the hadronic form factor in D0 decays using pole models, with new parameter estimates.

Findings

Measured pole mass m_pole = 1.854 GeV/c2 with uncertainties.

Determined modified pole scale alpha_pole = 0.43 with uncertainties.

Quantified statistical and systematic uncertainties in the form factor parameters.

Abstract

We present a preliminary measurement of the q2 dependence of the D0 --> K- e+ nu_e decay rate. This rate is proportional to the hadronic form factor squared, specified by a single parameter. This is either the mass in the simple pole ansatz m_pole = (1.854 +- 0.016 +- 0.020) GeV/c2 or the scale in the modified pole ansatz alpha_pole = 0.43 +- 0.03 +- 0.04. The first error refers to the statistical, the second to the systematic uncertainty.